The present invention relates to docking or securement devices, systems and methods for securing wheeled mobility devices (WMDs) used by persons with physical disabilities in both public and private transport vehicles.
The following information is provided to assist the reader to understand the invention disclosed below and the environment in which it will typically be used. The terms used herein are not intended to be limited to any particular narrow interpretation unless clearly stated otherwise in this document. References set forth herein may facilitate understanding of the present invention or the background of the present invention. The disclosure of all references cited herein are incorporated by reference.
An increasing number of people with disabilities use wheeled mobility devices (WMD) (e.g., traditional manual and powered wheelchairs, powered bases, scooters, strollers) as a means of accessing public and private motor vehicles. For many, the ability to remain seated in their WMD while riding in a transport vehicle is the only feasible means of gaining access to education, work or recreational activities. The vast majority of WMDs, both traditional and contemporary, are not designed to be used as seats in a transport/transit vehicle. The wheels, seat and frame structures and battery containers were not engineered to withstand the potentially high “g” forces of a crash. Furthermore, most WMDs do not have designated attachment points for securement to the vehicle and, therefore, securement, both in terms of strength and location on the frame, can often be haphazard and uncertain from a safety viewpoint. Therefore, most secured WMDs do not provide the WMD-seated occupant with an equivalent level of travel safety as that provided the non-disabled rider by a car, van, or transport vehicle seat.
It is generally recognized that both the occupant restraint and the WMD securement device must act together as an integral crash protection system. There are essentially two basic approaches to the securement of WMDs that are in common use today, attendant-operated securement systems and auto-engaging docking devices. The attendant-operated type is dominated largely by three or four-point strap-type devices that hook to various parts of the WMD frame. Problems quickly arise when there are no appropriate locations to attach the securement belts to the WMD. An example of this situation is encountered with scooter and power bases where molded plastic housings enclose the structural frame. Also, the requirement that an attendant or vehicle operator always be present and time required to secure the WMDs creates logistical problems for the transporter. Hunter-Zaworski K M, Ullman D G, Herlineg, D E. Application of the Quality Functional Deployment Method in Mobility aid Securement System Design: Volume 1. Transportation Research Institute, Oregon State University. Final Report-December 1992. NTIS Number: FTA-OR-11-0006-92-1. Additionally, test results have indicated that existing strap tiedown systems are at the upper limits of their capacity when tested at 30 mph/20 g loading. Fisher W E, Seeger B R, Svensson N L. Development of an Australian Standard for wheelchair occupant restraint assemblies for motor vehicles. Journal of Rehab Research and Development 1987; 24(3): 23-24. This implies that many heavier models of powered WMDs may not be secure at nominal crash load levels. Also, users of transport vehicles have expressed dissatisfaction with operators having to fumble around their legs and upper body while fastening or disengaging the strap devices. Because of the difficulty and inconvenience of using strap systems they are often simply not used at all, or are not fastened in a way that will provide adequate crash protection. Moreover, strap-type securement devices are inconsistent with the intent of Americans with Disabilities Act (ADA), which is to provide persons with disabilities increased access to community resources through improved independent use of public transportation systems.
Several docking-type securement devices are commercially available but use is limited largely to private vehicles. These devices have matching components, one attached to the WMD frame and the other (docking securement device) to the vehicle. Hunter-Zaworski K M, Ullman D G, Herlineg, D E. Application of the Quality Functional Deployment Method in Mobility aid Securement System Design: Volume 1. Transportation Research Institute, Oregon State University. Final Report-December 1992. NTIS Number: FTA-OR-11-0006-92-1. They offer increased user independence, but rely on having a location on the WMD to which one component (WMD adapter) of the securement system can be attached. As mentioned above, most WMDs do not have appropriate securement attachment locations. Also, since there is such a variety of WMDs, a large number of WMD adapter configurations must be provided by a third party manufacturer, each of which needs to be safety tested. To date, WMD manufacturers have not provided adapters for their products, mainly as a result increased liability and cost of producing and testing a different adapter for each model of WMD product.
Docking devices have been shown to work reasonably well for private vehicles in which the matching components can be individually configured. However, public vehicles must be able to accept any WMD to be universally applicable. Early docking devices represent a departure from the four-strap tiedown approach, and are the first step towards a more universal and user-independent solution. However, the existing docking designs do not provide a universal solution to the public transit problem, where the majority of WMDs are used
Efforts to foster the development of a universal industry design standard for the interface hardware between WMDs and docking-type securement devices by the Rehabilitation Engineering Research Center (RERC) on Wheeled Mobility at the University of Pittsburgh have led to development and publishing in 2005 of a voluntary international standard (ISO 10542-3) for wheelchair docking securement devices by the International Standards Organization (ISO), the disclosure of which is incorporated herein by reference.
However, the transportation of WMD users in North America remains in a state of chaos. The manifestations are that users are inconvenienced, transportation time and costs are unnecessarily high, legal liabilities are pervasive, and most importantly, user safety in many cases is seriously compromised. The ADA mandate of accessibility and safety, although laudatory in its intent, is technically not achievable with existing restraint and strap-type securement technology.
It is therefore desirable to develop improved devices, systems and methods for securing (and preferably auto-docking) WMD device within vehicles. Preferably, such devices, systems and method are compatible with the ISO 10542-3 industry standard.